In this review, we will be comparing KUBE 8b and SX-120, two Powered Subwoofer speakers from KEF and Cambridge Audio. Being Powered subwoofers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features of KEF KUBE 8b and Cambridge Audio SX-120 first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the KEF KUBE 8b and Cambridge Audio SX-120 compare and hopefully end up with enough arguments to decide which one of these subwoofers is the better choice for you.
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Drivers
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.KEF KUBE 8band Cambridge Audio SX-120 have the same driver set up: Both subwoofers have 1 x 8" drivers.
Frequency Response
KUBE 8b has a frequency range of 34-140 Hz whereas SX-120 has a frequency range of 34-150 Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Subwoofer class in our database.
Low Frequency
Subwoofer Speakers
High Frequency
Subwoofer Speakers
Cabinet Type
The KEF KUBE 8b has a Acoustic Suspension type cabinet. Acoustic Suspension aka Sealed type subwoofers have enclosures that are sealed hence no ports or holes exists on the cabinet. Sealed designs helps to provide more accurate and tight bass responses compared to ported designs. On the other hand the Cambridge Audio SX-120 have Bass Reflex type enclosure. Bass Reflex type subwoofers (aka Ported, Vented or Reflex Port) have enclosures that uses a port, hole or vent cut into the cabinet. Ported designs are generally more efficient than the Sealed designs.
Physical Specs
Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare KEF KUBE 8b's and Cambridge Audio SX-120's external dimensions. KEF KUBE 8b has external dimensions of 294.0 x 296.0 x 339.0mm ( 11-9/16 x 11-5/8 x 13-5/16inch) whereas Cambridge Audio SX-120 has external dimensions of 296.0 x 297.0 x 350.0mm ( 11-5/8 x 11-11/16 x 13-3/4inch) .
Cambridge Audio SX-120 is clearly the larger of the two speakers. Its body is 1mm wider, 2mm taller and 11mm deeper than KEF KUBE 8b.
Below you can see the front view size comparison of KEF KUBE 8b and Cambridge Audio SX-120 in scale.
Comparison image of KEF KUBE 8b and Cambridge Audio SX-120 Size and External Dimensions
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the KEF KUBE 8b is approximately 1003.4cm2 / 155.5inch2 and base area of the Cambridge Audio SX-120 is approximately 1039.5cm2 / 161.1inch2. The KUBE 8b requires 3% less surface area than the SX-120 which gives it a small advantage on placement in tight spaces.
Weight Comparison The weight of a subwoofer may become an important factor if you need to move and reposition the unit often to find the optimal positioning, also known as 'Subwoofer Crawling'. The KEF KUBE 8b weighs 11.36kg / 25lbs and the Cambridge Audio SX-120 weighs 7.73kg / 17lbs. This makes the KUBE 8b 47% heavier than the SX-120.
Here is a comparison of how KUBE 8b and SX-120's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of KEF KUBE 8b?
Here are the items that are included inside the box of KUBE 8b:
Powered subwoofer6.5-feet AC power cordSpeaker-level input blockUser ManualImportant Safety InformationWarranty Information
What's in the Box of Cambridge Audio SX-120?
Here are the items that come with the SX-120:
Powered subwoofer6-feet AC power cordGrille4 Spiked feetInstallation GuideImportant Safety Instructions
 Height |
294mm
vs
296mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1003cm2 (296x339mm)
vs
1039cm2 (297x350mm)
|
Takes less floor space |
 High Frequency Response |
150k Hz
vs
140k Hz
|
Generates higher frequency |
 Price per pair* |
319USD
vs
600USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
KEF KUBE 8b |
Cambridge Audio SX-120 |
| Brand |
KEF |
Cambridge Audio |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
70 watts |
| Frequency Response |
34-140 Hz |
34-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
70-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
8" |
| Woofer Composition |
Not given |
Treated Paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
40-140 Hz |
n/a |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
294.0mm (11.6") |
296.0mm (11.7") |
| Width |
296.0mm (11.7") |
297.0mm (11.7") |
| Depth |
339.0mm (13.3") |
350.0mm (13.8") |
| Weight |
11.36kg (25lbs) |
7.73kg (17lbs) |
| Enclosure |
Acoustic Suspension |
Bass Reflex |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
3 Years |
| Labor Warranty |
2 Years |
3 Years |